1. Field of the Invention
The present invention relates to a cerumen block for a sound delivery system such as a hearing aid, a communications device, or a multimedia device, and more particularly, the invention relates to an earpiece having a cerumen block for improved delivery of sound into the ear canal.
2. Brief Description of the Related Art
Sound delivery systems such as hearing aids, cellular telephones, and other sound transmitting systems employing earpieces are utilized to deliver sounds directly to the ear canal of the user. Such sound delivery systems include those worn by police, firefighters, secret service agents, and the like to receive sound transmissions from a remote location. Other sound delivery systems include the class of hearing aids which are used by the hearing impaired to amplify and process sounds. Traditional hearing aids include "in the ear" (ITE) hearing aid devices inserted into the ear of the user, "in the canal" (ITC), "completely in the canal" (CIC), and "behind the ear" (BTE) hearing aid devices which are attached behind the ear of the user. The BTE hearing aid devices generally include a flexible plastic tube connecting an amplification and processing device mounted behind the ear to an eartip positioned within the ear canal.
Many different types of eartips are available for fixing an end of a sound transmitting tube in the ear canal. Eartips may be custom made to fit within the ear canal of a particular user, however, these custom made eartips are expensive and can block the ear canal almost entirely causing a problem known as the occlusion effect. Other types of eartips include stock members which are generally used during a trial period when a hearing aid is being tested or while an ear mold is being made. These stock eartips may be formed of hard materials, rubbery materials, or foam. However, any eartip which is placed within the ear canal will have problems of blockage of the eartip sound output ports by cerumen (earwax).
Cerumen blockage of the sound output ports of an earpiece causes sound degradation and eventual failure of the sound delivery system to deliver sound to the ear canal. This degradation and eventual failure due to cerumen blockage is the most common cause of failure in sound delivery systems such as hearing aids. There are many different approaches commercially available for preventing the cerumen blockage of hearing aid sound output ports. One such blockage preventing method includes a sound transparent membrane which allows sound to pass through while blocking cerumen. Because of the thinness required of the sound transparent membrane to prevent sound attenuation, the membrane tends to be delicate and to tear or puncture easily.
Another type of cerumen blockage prevention system includes a mechanical assembly which can be periodically actuated to eject collected cerumen from the sound output ports to clear the output ports. One such mechanical actuated assembly includes a spring loaded cylindrical output port which slides over a pin to eject cerumen. The mechanical actuated assemblies for ejection of cerumen are complex and require periodic actuation to remove cerumen buildup. Another type of blockage protector is a replaceable "band aid" type protector which requires periodic replacement. The "band aid" cerumen protector includes a porous piece of material such as foam having pressure sensitive adhesive which is used to secure the foam over a sound output port. These "band aids" fill up with cerumen, blocking the sound but are easily peeled off and replaced. Thus, these devices must be maintained and there is an associated expense of periodic replacement. Finally, acoustic labyrinths have been used in the sound output ports of earpieces to reduce cerumen blockage. These acoustic labyrinths slow the occurrence of cerumen blockage but will still become clogged over time.
Accordingly, it would be desirable to address the problem of cerumen blockage of sound delivery output ports by a simple, reliable, and effective cerumen blockage device.